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Necessary assumption

(NA)

Stems that ask us to identify a claim that is required in order for the premises to support the conclusion.

Avg. 2.25 per section

“Which one of the following is an assumption that the argument above requires?”

9%
21%
37%
19%
14%

Avg. difficulty: 3.1

Correct answer criteria

  • Something that must be true in order for the argument's conclusion to follow from the premises.

Key tactics

  • Identify the conclusion and the premises
  • Think about why the conclusion doesn't have to be true even if the premises are true
  • Pay attention to new concepts brought up on the conclusion but not mentioned in the stimulus. The argument has to make some kind of assumption about those new ideas
  • Be open-minded; sometimes an argument can have many different necessary assumptions and it's hard to predict what the correct answer will be about
  • If you're uncertain about an answer, apply the negation test. Does the negation of the answer make it impossible for the conclusion to follow logically from the premises? If yes, then this answer is necessary and is correct

Answer choice tips

  • Be careful about extreme answers, since they often go beyond what the argument needs to make sense. Strongly worded answers can be correct, but be careful about them
  • Weak answers (e.g., "Some" "sometimes" "not always") are more likely to be correct than strong answers. When using the negation test, negating a weak statement ("some") always produces a strong statement ("none"), and strong statements are more likely to damage the conclusion

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Logical reasoning question types

Alternate explanation Analogy (LR) Argument part Bad authority Causal chain Causal mechanism Causal reasoning Circular reasoning Conditional reasoning Confusing sufficiency and necessity Correlation Diagram? Directionally wrong Eliminating options Equivocation Evaluate Except (LR) Failed alternate explanation False dichotomy Fighting the hypothetical Fill in the blank Flaw or descriptive weakening Illusory inconsistency Inference Internal contradiction Irrelevant corroboration Kick it up Lack of support v. false conclusion Link assumption Main conclusion or main point Math Mental state v. reality Method of reasoning or descriptive Miscellaneous (LR) Misdirected response Most strongly supported Must be false Must be true Necessary assumption Parallel flawed method of reasoning Parallel method of reasoning Part v. whole Phenomenon-hypothesis (LR) Plausibility Point at issue: agree Point at issue: disagree Principle PSA - find or complete the application PSA - find the rule Quantifier Relative v. absolute Resolve reconcile or explain Rule-application Sampling Source attack Strengthen Sufficient assumption Time Unwarranted assumption Value judgment Weaken Weighing factors

Reading comprehension question types

Analogy (RC) Application Art Author’s attitude Author’s perspective Comparative Critique or debate Describe approach Describe organization Describe relationship Except (RC) Humanities Implied Law Logical continuation Main point Meaning in context (of word, phrase, or idea) Miscellaneous (RC) Other’s perspective Phenomenon-hypothesis (RC) Principle or generalization Problem-analysis Purpose in context (of word, phrase, or idea) Purpose of paragraph Purpose of passage Science Single position Spotlight Stated Structure WSE (RC)

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